Injuries have meant we've not been able to field the same back four in the first six games of the season with Steve Carr, Christian Ziege, Anthony Gardner, Dean Richards and Mauricio Taricco all missing games.
Gary reckons the changes have taken their toll with a spell of one goal conceded in three games followed by five in our last two.
All concerned, not least Glenn Hoddle, know we need to tighten up again.
Big 'Doc', who came off the bench against West Ham after another defensive injury, this time to Chris Perry, reflected: "The goals we've conceded have been very disappointing, especially the second one against West Ham.
"We just switched off on a set-piece when we are normally good at defending them. All we can do is get out there on the training ground and put it right.
"But we've had an unsettled defence. Tano and Chrissy Perry came off on Sunday, Deano has got a knock, Anthony Gardner missed Charlton with an injury, Carry, we've not had any real continuity there. I think once we get that, we'll look a lot more solid.
"We're scoring goals though, Robbie's looks as if he's on fire and we're winning games, so they are the positives we have to take out of it."
Gary Doherty predicts that we'll regain our defensive solidity once we have a settled back four or five.